In a development that could complicate ongoing peace talks to end two separate conflicts in Sudan, the government in Khartoum said that it believes the Sudan People's Liberation Army (SPLA) is actively giving military assistance to the main rebel groups in western Darfur in their year-long fight against Khartoum.

The Sudanese government is reacting with anger to Saturday's first-ever meeting between the leader of the southern-based SPLA, John Garang, and the leader of the Darfur rebel Sudan Liberation Movement (SLA), Abdulwahid Mohammed Ahmed.

The meeting, which took place in neighboring Eritrea, followed a suspension in the months-long talks in Kenya between the SPLA and Khartoum. The talks are aimed at ending the 21 year civil war in the oil-rich south that has killed and displaced millions of people.

On April 17, the head of the Sudanese delegation, Vice President Ali Osman Taha, left the talks for a weeklong consultation in Khartoum. Last Thursday, SPLA leader John Garang also left Kenya, but he did not say where he was going.

Sudanese Foreign Minister Mustafa Ismail said that the fact that Mr. Garang left the talks to meet a rebel leader from Darfur shows that southern-based rebels are not negotiating in good faith at the Kenyan-sponsored talks.

He said that his government has proof that the SPLA is actively assisting the rebels in Darfur in an effort to destabilize and eventually topple the government.

"This has been a policy of the SPLA for a long time: to move forward to the north," he said. "Then, you weaken the government. The SPLA itself is part of the rebellion in Darfur. They start to train some rebels from Darfur in camps in areas which are controlled by the SPLA and Eritrea."

Sudan has long accused Eritrea, which has a hostile relationship with Khartoum, of providing training facilities and arms to the SPLA in the south, to rebel forces in Darfur and another rebel group called Beja Congress in the east.

SPLA's Kenya-based spokesman, Samson Kwaje, denied that his group is fueling the rebellion in Darfur along with Eritrea.

He said that SPLA leader John Garang met with SLA rebel leader Mohammed Ahmed on Saturday to give the western Darfur rebels moral and political support.

"Yes, we morally and politically support them because they are suffering the same marginalization that the people of the south have been subjected to," he said. "But the SPLA is not assisting the rebels in Darfur with arms. We're not fighting there, and we're not arming anybody."

Sudan's war in the south broke out in 1983 amid rebel accusations that the Arab Muslim government in Khartoum left the mostly Christian and animist Africans in the south impoverished and politically disenfranchised.

In February 2003, two African Muslim rebel groups in Darfur took up arms against Khartoum, complaining of similar regional neglect. Since then, Darfur has become the site of what the United Nations called the worst humanitarian catastrophe in the world, with nearly one million people displaced by the fighting.

Human rights groups also accused Khartoum of helping local Arab militias commit gross human rights abuses in Darfur. The Sudanese government denies the charge.